In Sweden, unusually warm temperatures have combined with little to no rainfall to stoke severe wildfires in several parts of the country. The fires have been raging since July 15. Some may have started naturally, but others are likely to have been caused by the use of disposable barbecues (link in Swedish).

It’s one of the the worst wildfire outbreaks Sweden has suffered, and the country’s authorities have called for help. France, Germany, Denmark, and Poland have sent in firefighters,...